The invention relates to reinforced "C"-shaped hand-rail made of plastic material for use with escalators and moving pavements and the like.
As known, the presently used escalator hand-rails are made of rubber, into which textile-, in given case metal-insert, or steel band, or their various combinations are built in as reinforcement.
Thus for example the rubber hand-rail of the escalator according to the West-German patent specification No. 1 101 717 is provided with a vulcanized steel band of suitable length for clamping the teeth of the driving wheel and to be driven synchronously with the escalator strap.
The moving hand-rail according to the West-German patent specification No. 860 701 contains a metal insert to prevent the elongation. This insert is a perforated endless steel band running parallel with the shaft of the driving wheels along the length of the hand-rail.
An escalator hand-rail with a coloured cover is described in the English patent specification No. 1 163 112, reinforced with a layer of cord fabric to eliminate the elongation.
According to the French patent specification No. 1 419 483 glass cloth inserts are built into the rubber material of the escalator hand-rail to prevent elongation and to take up the tensile load. At least the warp of the textile has to be made of fibreglass. Since the glass cloth has poor adhesive characteristics, the adhesion, specially at blind splicing, is facilitated with traditional rubberized textile-layers between the glass cloths.
Finally the escalator hand-rail according to the French patent specification No. 1 340 585 differs from the traditional solutions in that its visible surface is provided with indentations, knurls, letters, or figures for easier noticeability.
The sliding surface of the hand-rail is generally made of textile according to the known solutions.
The common drawback of the known escalator hand-rails is that they can be no longer repaired, when the textile sliding layer is worn down, furthermore, owing to the construction of the hand-rails, the position of the neutral layer is asymmetrical, consequently the sliding ends of the "C" profile are exposed to complex dynamic loads. This expedites the fatigue of the system, and thereby separation of the textile layers.
Construction of the hand-rail with textile insert is extremely labour-intensive, and requires precise preparatory activities.
For reducing the elongation of the escalator hand-rails, the constructions comprising the combination of textile and steel wire have been generally used further complicating the production process of escalator hand-rail.
The blind splicing of the systems used according to the present practice requires similarly labourintensive stepping or buffing bruising activities. The layers of raw rubber mixture between the stepped ends are vulcanized together in splicing press on the site of the assembly. Since the continuity of the reinforcing layers in the ends of the vulcanized rubber hand-rail stops, these spots represent weak points compared to the other parts of the hand-rail.